State machines will now throw exceptions if errors are encountered
when loading the XML file.
This includes:
- Unknown <source> or <target> states referenced by transitions
- States and transitions without <name> elements
- Transitions without <target> or <condition> elements
- State machines with fewer than two states
Previously the state machine would load and then crash when hitting
such malformed states or transitions. Now it will refuse to load,
while providing useful error messages as to the problem.
Stuart Buchanan
f076c43b90